While looking for the Pyramid, keep going to almost the very end of Lee Drive and you'll see the Pyramid past the railroad tracks in the distance to your left.
And since you're visiting the Pyramid, take your time going down Lee Drive. Many Confederate fighting positions are still visible, including an artillery site and trench works. I found this to be more interesting than the Pyramid itself. While you can see the Pyramid from the road you can't get close to it, since it's on the other side of an active Amtrak line.
About the battle: While the Union's river crossing on Day 1 and heroic attack on the Sunken Road at Marye's Heights on Day 3 get plenty of attention, Day 2 is often overlooked. In fact Meade's attack against the southern Confederate flank on Day 2 almost broke through their lines, but failed mostly because of poor communication between Union commanders. The "pyramid" stands near the point of the Union's greatest penetration.
The "Slaughter Pen" (which has its own Yelp entry) is on the opposite side of the wood line. Unfortunately the Confederate and Union positions are separated by the railroad, so you can't walk the entire length of the battlefield.
Funny thing about the Pyramid - it was actually built by southerners. The idea for a monument was pitched by the Confederate Memorial Literary Society to Virginia railroad execs who sought to memorialize the battle in a location visible to train travelers. The pyramid shape is based on the monument to the Unknown Confederate dead in Richmond. read more